An attempt was made to distinguish between capacity and motivational interpretations of individual differences in children's creativity. Creativity tasks required the child to name as many ideas as he could that met a simple problem requirement. Tasks were given under "base line" conditions and with a reward of one cent for each idea given. If task motivation is the critical determinant of performance, reward should decrease the differences between high and low scorers by decreasing the range of motivation with which the task is approached. However, if these individual differences reflect capacity, reward should increase or leave unchanged the difference in number of ideas given by more and less fluent children. Reward led to an increase in mean number of ideas which was consistent across levels of creativity. Thus, while motivating conditions may alter the level at which the group performs, the data suggest that individual differences in performance derive from differences in capacity rather than motivation for divergent ideational producation. (Author/JM)